What are the recommended settings to successfully implement VoIP over 3G/4G data connection. Assume we are talking about using Polycom phones, and the 3G/4G data connection comes from a Cradlepoint router that is plugged in with AC power and has high gain antennas. The device will be stationary, so we will not have to worry about tower handoff?s breaking the connection. This will be for fixed wireless. I have read to use G.729 codec, and TCP for signaling to bypass firewalls. Besides that, what other settings are recommended? Changes in MTU? Changes in voice payload ms? Is there a better codec to use? Header compression? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20140718/2e48d8e2/attachment.html>
Depends on the carrier. Verizon Wireless appears to activly block SIP. G729 codec is needed on 3G and is a good idea on 4G. I use TLS and SRTP to work around carrier stupidity. I also use a non-standard port for TLS. It mostly works much of the time. Don?t get BRIA, every time your registration is dropped it will popup a notification. From: asterisk-users-bounces at lists.digium.com [mailto:asterisk-users-bounces at lists.digium.com] On Behalf Of Tech Dude Sent: Friday, July 18, 2014 1:00 PM To: asterisk-users at lists.digium.com Subject: [asterisk-users] VoIP over 3G/4G Data What are the recommended settings to successfully implement VoIP over 3G/4G data connection. Assume we are talking about using Polycom phones, and the 3G/4G data connection comes from a Cradlepoint router that is plugged in with AC power and has high gain antennas. The device will be stationary, so we will not have to worry about tower handoff?s breaking the connection. This will be for fixed wireless. I have read to use G.729 codec, and TCP for signaling to bypass firewalls. Besides that, what other settings are recommended? Changes in MTU? Changes in voice payload ms? Is there a better codec to use? Header compression? -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.digium.com/pipermail/asterisk-users/attachments/20140718/6bd7ada3/attachment.html>
On 18-07-14 17:59, Tech Dude wrote:> What are the recommended settings to successfully implement VoIP over > 3G/4G data connection. Assume we are talking about using Polycom phones, > and the 3G/4G data connection comes from a Cradlepoint router that is > plugged in with AC power and has high gain antennas. The device will be > stationary, so we will not have to worry about tower handoff?s breaking > the connection. This will be for fixed wireless. > > I have read to use G.729 codec, and TCP for signaling to bypass > firewalls. Besides that, what other settings are recommended? Changes > in MTU? Changes in voice payload ms? Is there a better codec to use? > Header compression?Use TLS/SRTP so the carrier can't do packet inspection/snooping and mess with or block your VoIP connections. They might throttle/block port 5060 and 5061 anyway in which case you should use different ports. I use Asterisk 11 with TLS/SRTP, G.722 and Android phones (4G, CSipSimple or Bria), iPhones (4G, Bria) and Polycom phones. G.722 on inter-office calls has been working great so no need for G.729 and Asterisk uses standard alaw/ulaw for regular PSTN calls. I use TCP, have made no MTU changes and use standard 20ms voice payload. Packet loss, latency and jitter are the enemy. Your router might be top notch but if the cell tower is overloaded and experiences too much packet loss, delays of more than 150ms and lots of jitter than you may get crappy sound quality. If possible, get some prepaid 4G sim cards for your router from different carriers and test which carrier consistently provides the best signal, least delay, packet loss and jitter. HTH, Patrick